Make views_examples_with_context_exe run with linux_chromeos

BUG=139313
TEST=None
R=ben@chromium.org

Review URL: https://codereview.chromium.org/26410002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227651 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227651
Simplify VideoFrameStream stopping process.

When VideoFrameStream::Stop() is called, invalidate all existing weak pointers,
satisfy all pending callbacks and start to stop DecryptingDemuxerStream and/or
VideoDecoder right away.

This also fixes the issue where VideoFrameStream::Stop() is called when
DecryptingDemuxerStream is in kWaitingForKey state.

BUG=304260,304577,303835
TEST=Added a test where VFS::Stop() is called when DDS is waiting for a key.

Review URL: https://codereview.chromium.org/26177002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227652 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227652